(i) Field of the Invention
The present invention relates to a lock device for fixing a rotating portion in a piece of furniture in which the rotating portion is rotatable between a substantially horizontal in-use position and a substantially vertical storage position, and relates to the piece of furniture including the lock device.
(ii) Background Art
A typical conventional piece of furniture includes a rotating portion, such as a top panel of a desk or a seating board of a chair, and a leg portion that supports the rotating portion. In the furniture, the rotating portion is supported by a leg portion so as to be rotatable around a horizontal axis between a substantially horizontal in-use position and a substantially vertical storage position. There have been proposals of a piece of furniture including a lock device for fixing the rotating portion at the in-use position or the storage position.
An example of such a lock device includes a lock member, a receiving member, a biasing element, and an operation lever. The lock member is provided so as to be rotatable relative to the rotating portion. The receiving member having an engaged surface engageable with the lock member is provided to a leg portion. The biasing element biases the lock member in a direction of engaging with the receiving member (an engaging direction). The operation lever operates the lock member in a direction of departing from the receiving member against a biasing force of the biasing element. The receiving member is configured such that the engaged surface slants in a direction of gradually increasing a pressure imposed by the engaging surface of the lock member on the engaged surface of the receiving member as the lock member is rotated in the engaging direction.